Road tars or the like and methods of making them



Patented Dec. 30, 1941 UNITED STATES PATENT'OFFICE 1 ROAD Tans on THE MAKING Vaman R. Kokatnur, New York, N. Y., assignorto Autoxygen Inc., New York, N. Y., a corporation of New York LIKE AND METHODS OF THEM No Drawing. Application September 3, 1935,

Serial No. 38,965

8 Claims. (Cl. 106-269) ly more expensive than even a high priced, high melting point tar.

An object of the present invention is to prowhich will have a high melting point to prevent stickiness in the summer time and a low freezing point to reduce the danger of cracking at winter temperatures.

Another object is to provide a road tar containing certain polarized groups having a natural affinity for the surface of the road to be coated, so that the material will very firmly adhere to the road surface or impregnate the road surface. In other words, the adhesive connection between the coating material and the coated surface is greatly enhanced.

Another object is to provide a road coating material of the character above noted, which, when applied to a concrete road, will actually serve to waterproof the concrete and thereby prevent moisture from finding its way into crevices in the concrete and splitting the concrete in freezing weather. The coating material contains certain agents which react by penetration with the concrete to form a very firm cementitious bond between the coating material and the concrete as well as to waterproof the latter.

Another object is to produce a non-sticky coating material which may be conveniently handled and applied to the road in various ways.

An important feature of the invention is the use of waste oil productsinthemanufacture of the tar. Literally millions of gallons of partially decomposed or dirty lubricating oil are annually wasted by draining the crank cases of automobiles. Even the disposal of this waste material is a problem to the ordinary service station where crank cases are usually drained.

By my present process I am able to take these waste lubricant oils with their carbon impurities, with the light fractions which have been cracked out by the heat of the combustion chambers and with any amount-of extraneous dust or dirt in .vide a road tar which will be quite inexpensive,

them and without purification thereofconvert them into road tars of high melting point and low freezing point. The tars made in accordance with my invention are primarily in the form of gels. They are homogeneous aside from such impurities as may be present in them, and after they have been sprayed on the road or used to impregnate the surface of the ground they retain substantially their original gel structure so that they definitely stay on location, This type of coating material or impregnating oil is particularly well suited for use on airplane landing fields because it not only kills the dust on such fields, but affords a very hard and substantial surface, which materially facilitates both landings and takeoffs. This is in direct contradistinction to the present airport surfaces where only a few hard surface runways are available and where heavy rains make the remainder of the field absolutely unsuitable for takeoff purposes and dangerous for landing purposes.

In accordance with a preferred embodiment of the invention I use an anhydrous metal alkali soap and combine it with the waste oil products or other relatively low melting point tarry materials, to produce a homogeneous high melting point gel. Impurities in the waste oils or other oily materials employed arepf no moment. The soap is combined with the tarry materials at a temperature which makes the presence of lighter fractions unimportant, and it is the soap content of the gel which furnishes the polarized groups with any type of surface. Such groups materially increase the tenacity with which the tarry substances adhere to the surface, and in the case of concrete roads the alkali soap content of the gel reacts with the lime and magnesium of the concrete to form metal soaps in the interstices of the concrete and very firmly bond the surfacing material to the concrete to afford a waterproof surface.

Ordinarily the freezing point of these gels is so low that they will not freeze much above zero. Since they prevent any moisture from gaining access to the interstices of the concrete, cracking of concrete roads even at extremely low temperatures is substantially inhibited.

In other words, I have discovered a process by which I am able to use the cheaper grade of tars or waste fuel oils and evolve aproduct which is not only devoid of the disadvantages which haveheretofore characterized low melting point The following example explains in detail a satisfactory method of producing a tarry road surfacing material having the desired-characteristics, but it is to be understood mat the example is merely typical of a satisfactory commercial process, and that various departures from the details of this process are within the scope of the invention.

I dissolve 100 parts of fatty material, such as coconut oil, tallow or fish oil. or the fatty acids of any of such oils, in a hydrocarbon diluent, such for instance as kerosene. Approximately 200 parts 'of kerosene, are preferably used, it being understood that the kerosene may be replaced by any equivalent material having an approximately similar boiling range. This solution is placed in a still and about 14 parts by weight of caustic soda, preferably in a dry pulverulent or iiakey form, are added. The mass is heated and agitated until the kerosene begins to boil. A partial pressure distillation effect is had so that substantially all of the water originally present orall of the waterliberated by the reaction collect in crevices of the the concrete upon freezing.

Another satisfactory method of using this gel is to mix the gel thoroughly with sand to form a. substantially dry composition which may sprinkled on the surface to be treated and then,

traversed by a hot roller to remelt the tarry soap gel and permit resetting of this gel in suclr a fashion that it is firmly bonded with the sand which has been combined with it as well as throughly bonded with the surface to which the dryvtarry sand mixture has been applied.

By merely heating these gels. they may handled in the same manner as ordinary low melting point road tars, that is to say, they may be spread directly on the ioad and sprinkled" over withs'and, or the road may be covered with sand 'upon which the hot tarry or melted gel is sprayed or spread. v I

While as above suggested the soap forming method rather closely follows that disclosed in my prior patient, it is not ,necessary to exercise distills off with the kerosene. In some cases as much as half orthree-quarters of the kerosene must be distilled off in order to effect complete removal of the water together with a portion or all of the glycerin liberated by the reaction. When no more water'is observed in the distillate, or when sufiicient kerosene has been driven off so that no more water can be present in the distillate, the distillation is stopped and to the saponified residue in the still I add 500 to 1000 parts of a heated tarry material, road oil or waste lubricant oil. Heating and agitation are continued until the entire mass becomes homogeneous and the mass upon cooling forms a gel. The general method of producing the saponi-' fled anhydrous residue is disclosed in my prior 'Patent 1,753,659 of April 8, 1930, and such a method of soap formation is preferred, although it is to be understood that it is within the scope of the invention to use any suitable method for producing a substantially anhydrous .soap of either a metal or an alkali metal.

' moval of all the water, and from a commercial standpoint it is desirable to remove nearly all the glycerin because of the value of this material when recovered as a pure by-product.

While metallic soaps as well as alkali metal soaps may be used in the material, I believe that the alkali metal has certain advantages particularly in that it is soluble in water and gradually permeates into the cementitious bed and changes its alkali to the metal in the interstices of the concrete.

In this example the proportion of soap to the oily road material is between 10 to 20%, but the proportions may be considerably varied without departing from the spirit of the invention.

So far as I have been ableto determine there should neverbe less than 5% of soap, and the use of more than 35% is not desirable because of the cost involved.

Instead of using caustic soda various other alkalies, such for instance as caustic potash, alkali earth and hydroxides of calcium and magnesium, may be substituted.

There are various methods by which this gel may be applied to the surface to be treated. Where the gel is to be applied to a concrete surface it may be slightly heated and mixed with a dry cement and spread upon the road in the form of a paste. The addition of the cement to the material promotes the reaction between the soap and the lime and magnesium in the concrete and effects a thorough bonding of the road surfacing material with the concrete road. This addition of cement to the tarry substance and which is spread-upon the road effectively Waterproofs the road due to the fact that as above suggested the alkali soaps react by penetration with the concrete to form a metallic soap in the interstices of the cementitious material. Water cannot get under such a coating and consequently cannot Many changes and alterations might be made in the-method of producing these materials without departing from the spirit of the invention or the scope of the appended claims.

Having thus described my invention what I claim as new and desire to secure by letters Patent is:

l. A road surfacing materialcomprising a gel composed of soap in the interior phase and tarry material of mineral origin inthe exterior phase, said gel being also characterized by being anhydrous and by having a higher melting point and lower freezing point than said tarry material and said soap being in the interior phase.

4. A road surfacing material comprising a gel formed of approximately parts anhydrous soap, not more than 200 parts kerosene, and 500' to 2000 parts waste lubricant oil, said oil being concrete and crack a the interior phase.

5. The method of preparing a road surfacing material which comprises dissolving a soapi'orming material in a hydrocarbon diluent of the boiling range of kerosene, distilling suflicient of said diluent in the presence of a metalhydroxide to drive off all the water present or produced in the reaction and thus to produce an anhydrous soap, adding to said soap a tarry material of mineral origin and heating the whole with accompanying agitation to produce a homogeneous gel.

6. The method of preparing a road surfacing material which comprises dissolving a soap-form,- ing material in a hydrocarbon diluent of the boiling range of kerosene, distilling sumcientof said diluent in the presence of a metal hydroxide to drive of! all the water present or produced in the reaction and thus to produce an anhydrous soap, adding to said soap a tarry material of mineral origin, and heating the whole with accompanying agitation to produce a homogeneous gel,

the proportions of said materials being in the order of 100 parts of soap-forming material to 25 500 to 2000 parts of tarry material.

7. The method of preparing a road surfacing material .which comprises dissolving approximately 100 parts of a fatty soap-forming material in appronmately 200 parts of kerosene, adding a suflicient quantity of a metal hydroxide to saponify said fatty material, distilling suf-' companying agitationto produce a homogeneous gel.

8. The method of preparing a road surfacing material which comprises dissolving a soapforming material in suitable proportions in a tarry material of mineral origin. adding a hydrocarbon diluent of the boiling range of kerosene and distilling a suflicient amount of the said diluent in the presence of an alkali hydroxide to drive oifall the water present and produced in the reaction, and continuing heat and agitation to produce a homogeneous gel.

VAMAN R. KOKAI'NUR. 

